LAUSR

Abstract The precise control of molecular orientation is a major route used to improve the performance of organic photovoltaic (OPV) cells. Herein, we attempt to apply molecular orientation control method to OPV cells using small molecules based on an oligothiophene (DRCN5T) fabricated by wet processing to improve the solar cell performance. The light absorbance of DRCN5T molecules was enhanced by their conversion to face-on molecular orientation, resulting in bulk heterojunction OPV cells with 10% higher power conversion efficiency than that of cells containing DRCN5T with edge-on molecular orientation. Our results suggest a route to develop highly efficient OPV solar cells fabricated by wet processing through precise control of molecular orientation.